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1

Measurement of the Heat of Reaction of Polytetrafluoroethylene/Aluminum Composites Based on Laser Initiation

Li S., Wu Y., Lin Q., Huang C., Yang S., Li J.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

534--546

EN

Polytetrafluoroethylene/aluminum (PTFE/Al) composites are reactive materials which can release energy due to exothermic chemical reactions initiated under shock loading conditions. In order to accurately measure the potential maximum heat of reaction of PTFE/Al composites in an inert atmosphere, we propose in this paper a heat of reaction measurement system based on laser initiation. Our results show that the measurement system successfully initiates the chemical reaction between PTFE and Al in an argon atmosphere. The comparison between theoretical calculations and experimental data demonstrates that our measurement method is highly accurate and exhibits excellent consistency. Thus, the heat of reaction measurement system based on laser initiation is applicable for measuring the heat of reaction of PTFE/Al composites and also other complicated reactive materials.

2

Influence of Processing Techniques on Mechanical Properties and Impact Initiation of an Al-PTFE Reactive Material

Feng B., Fang X., Li Y.-C., Wu S.-Z., Mao Y.-M., Wang H.-X.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 4

989--1004

EN

Reactive materials (RMs) or impact-initiated materials have received much attention as a class of energetic materials in recent years. To assess the influence of processing techniques on mechanical properties and impact initiation behaviors of an Al-PTFE reactive material, quasi -static compression tests and drop-weight tests were performed. Scanning electron microscopy (SEM) was used to identify the characteristics of the interior microstructures of the Al-PTFE samples. A sintering process was found to transform Al-PTFE from a brittle to a ductile material with an increased elasticity modulus (from 108-160 MPa to 256-336 MPa) and yield stress (from 12-16 MPa to 19-20 MPa). Increasing the molding pressure from 36 MPa to 182 MPa increased the elastic modulus of all Al-PTFE samples and also the yield stress of unsintered ones. Unsintered samples in general required less energy to initiate than sintered ones. As the molding pressure increased, the impact initiation energy for sintered Al-PTFE fell from 96 J to 68 J, whereas the initiation energy for unsintered Al-PTFE rose from 68 J to 85 J. PTFE nanofiber networks observed in sintered samples formed under the higher molding pressures could contribute to the opposite trends observed in the impact initiation energy of unsintered and sintered Al-PTFE samples.

3

Processes and reactive materials used in PRB technology

Suponik T.

Górnictwo i Geologia

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2011

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T. 6, z. 2

227-238

EN

The processes used the most often in PRB technology are presented and described in the paper. These processes are: redox reactions, precipitation by pH control, adsorption and biochemical reactions. They proceed in the reactive materials listed in the paper. The list of these materials were obtained on the basis of laboratory and field research made by authors of different kind of papers. While proper reactive material is selected, it should pay attention the type of contaminants presented in the groundwater. Reactivity, hydraulic performance, stability, environmentally compatible by-products, availability and price are the factors that decide which reactive material ought to be used in the specific condition.

PL

W artykule przedstawiono i opisano najczęściej stosowane procesy w barierze reaktywnej technologii PRB. Do procesów tych należą: reakcje redox, wytrącanie przez regulację pH, adsorpcja oraz reakcje biochemiczne. Procesy te przebiegają w materiałach aktywnych przedstawionych w pracy. Listę materiałów otrzymano na podstawie badań laboratoryjnych i polowych wykonanych przez wymienionych w artykule autorów różnych prac. Podczas wyboru odpowiedniego materiału aktywnego powinno zwracać się uwagę na rodzaj zanieczyszczeń znajdujących się w wodach gruntowych. Czynnikami decydującymi o wyborze najlepszego dla określonych warunków rodzaju materiału aktywnego są jego aktywność, zdolność filtracyjna, stabilność, zgodność ze środowiskiem (materiał aktywny nie powinien ujemnie wpływać na środowisko przyrodnicze) oraz dostępność i cena.